Laser control method and laser irradiation apparatus using same

ABSTRACT

Provided are a laser control method and a laser irradiation apparatus thereof, which can efficiently perform the laser treatment. The laser control method includes a setting step of setting a guide path on a surface of an object; and an irradiating step of irradiating a laser onto the surface of the object corresponding to the guide path, wherein at least one of a fluence or a frequency of the laser is gradually increased at the beginning stage of the laser irradiation and at least one of the fluence or the frequency of the laser is gradually decreased at the end of the laser irradiation.

TECHNICAL FIELD

The present invention relates to a laser control method and a laserirradiation apparatus thereof, which can control the characteristic ofthe laser irradiation.

BACKGROUND ART

Today, a variety of laser treatment methods by irradiating the laserbeam on the skin have been developed to achieve the purpose oftreatment, etc., and have been still actively studying a medical laserapparatus for use the laser treatment methods.

The treatment methods using the laser has been using for a variety ofpurposes such as to promote hair growth or prevent hair loss, skin peel,skin regeneration, skin whitening, wrinkle or spot removal, or stainremoval, etc.

However, a user, such as a physician, manually operates the lasertreatment apparatus to perform the treatment in the conventional art.

Accordingly, there is a problem in that the reliability of the treatmentmay be decreased by lowering the accuracy of the treatment.

In addition, conventionally, there is an additional problem that of thetreatment time for taking the laser is excessively too long.

DISCLOSURE Technical Problem

An object of the present invention is to provide to a laser controlmethod and a laser irradiation apparatus thereof, which can efficientlyperform the laser treatment.

Technical Solution

A laser control method includes a setting step of setting a guide pathon a surface of an object; and an irradiating step of irradiating alaser onto the surface of the object corresponding to the guide path,wherein at least one of a fluence or a frequency of the laser isgradually increased at the beginning stage of the laser irradiation andat least one of the fluence or the frequency of the laser is graduallydecreased at the end of the laser irradiation.

A laser irradiation apparatus includes a motion controlling unit forsetting a guide path on a surface of an object; and a robot arm, mountedwith an end-effector, for applying a laser to the surface of the objectcorresponding to the guide path, wherein at least one of a fluence or afrequency of the laser is gradually increased at the beginning stage ofthe laser irradiation and at least one of the fluence or the frequencyof the laser is gradually decreased at the end of the laser irradiation.

On the other hand, the laser irradiation method is making a computerprogram for performing him may be provided in the program itself orstored in a recording medium, it can be performed by the laserirradiation apparatus according to an embodiment of the presentinvention.

In addition, the laser irradiation apparatus may use a wired or wirelessnetwork such as the Internet may be controlled as described above inconjunction with an external server.

Advantageous Effects

A laser irradiation apparatus using a robot arm and a method thereofaccording to the present invention have effects that of improving theaccuracy of the laser treatment and effectively reducing the operatortime required for the laser treatment.

According to the embodiment of the present invention, the precision andstability of the laser treatment may be improved, and the operating timerequired for the laser treatment may also be reduced.

In addition, the laser irradiation apparatus may be stably operated bygradually increasing or decreasing the fluence or frequency of the laserin the beginning stage and the ending stage of the laser irradiation.

DESCRIPTION OF DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

FIGS. 1 to 3 are block diagrams for explaining embodiments for theoverall structure of a laser irradiation apparatus according to thepresent invention.

FIGS. 4 to 29 are views for explaining the construction and theoperation of a laser irradiation apparatus according to embodiments ofthe present invention.

BEST MODE

Detailed exemplary embodiments of the present invention will bedescribed with reference to the accompanying drawings.

The present invention may be modified in various ways and implemented byvarious exemplary embodiments, so that specific exemplary embodimentsare illustrated in the drawings and will be described in detail below.However, it is to be understood that the present invention is notlimited to the specific exemplary embodiments, but includes allmodifications, equivalents, and substitutions included in the spirit andthe scope of the present invention.

On the other hand, although the first and/or the terms of the second andso on in the present invention can be used in describing variouselements, but the above elements shall not be restricted to the aboveterms. These terms are only to distinguish one component from othercomponents, for example within that range departing from the scope ofthe concept of the present invention, a first element could be termed asecond element, Similarly, the second component may be named as a firstcomponent.

As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items.

It will be understood that when an element is referred to as being“connected” or “coupled” to another element, it can be directlyconnected or coupled to the other element or intervening elements may bepresent. In contrast, it will be understood that when an element isreferred to as being “directly connected” or “directly coupled” toanother element, there are no intervening elements present.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms are intended to include the plural formsas well, unless the context clearly indicates otherwise.

It will be further understood that the terms “comprises,” “comprising,”“includes,” and/or “including,” when used herein, specify the presenceof stated features, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, integers, steps, operations, elements, components,and/or groups thereof.

Unless otherwise defined, all terms used herein have the same meaning ascommonly understood by one of ordinary skill in the art to which thisinvention belongs. It will be further understood that terms, such asthose defined in commonly used dictionaries, should be interpreted ashaving a meaning that is consistent with their meaning in the context ofthe relevant art and will not be interpreted in an idealized or overlyformal sense unless expressly so defined herein.

In the following description, it is explained as an example that thelaser is irradiated to the facial skin of the patient for ease ofexplanation, but the apparatus and the method according to the presentinvention can be applied whatever as long as irradiating the laser beamon the surface of a given object.

The accompanying drawings are intended to illustrate aspects of thepresent invention, but the scope of the present invention is not limitedto this. In addition, the attached drawings will be noted that theportion or component is disposed is enlarged/reduced to better explainthe characteristics of the present invention.

Hereinafter, a laser irradiation apparatus using a robot arm and amethod thereof according to the present invention is described in detailwith reference to the accompanying drawings.

FIGS. 1 to 3 are block diagrams for explaining embodiments for theoverall structure of the laser irradiation apparatus according to thepresent invention.

Referring to FIG. 1, the laser irradiation apparatus 10 may include ascanner 300, a robot arm 100, and a controlling unit 200.

The scanner 300 may collect raw data by scanning an object. Here, theraw data may include two-dimensional image and depth information.

The two-dimensional image may include color information, the diagnosisof the particular condition, such as telangiectasia may be possibleaccording to the color information of a patient's skin. Further, thescanner may detect the size, location, or depth information, etc. forpores, scars, or wrinkles of the patient's face using thetwo-dimensional images and the depth information.

The scanner 300, as shown in FIG. 2, may include a color sensor 310 forphotographing the two-dimensional color images, and an IR projector 320and an IR sensor 330 for obtaining the three-dimensional depth data.

If the IR projector 320 may irradiate the IR light on the surface of anobject 400, that is the surface of the patients' skin, the IR sensor 330would obtain the depth data by detecting the IR light reflected from thesurface of the object 400.

The color sensor 310 may obtain the two-dimensional color image byphotographing the surface of the object.

The robot arm 100 may have an end-effector (EE) 101, as shown in FIG. 3,and irradiates the laser on the surface of the object 400 according tothe control of the controlling unit 200. Specifically, the robot arm 100may irradiate with the laser to the surface of the object 400 inresponse to a guide path (GP) through the end-effector 101. Such therobot arm 100 may be considered as a manipulator.

The controlling unit 200 may control the overall function and operationof the laser irradiation apparatus 10.

The controlling unit 200 may include a vision controlling unit 210 and amotion controlling unit 220.

The vision controlling unit 210 may receive the raw data having thetwo-dimensional image and the depth information transmitted from thescanner 300, and configure the three-dimensional image of the object 400on the basis of the raw data.

Here, the origin position of the raw data and the direction of thecoordinates may vary depending on the object 400, for example, the shapeand volume of the face, or various causes such as the scan startingpoint of the scanner 300, etc.

In addition, the vision controlling unit 210 may adjust the coordinatesin alignment for the raw data. For this adjustment, the visioncontrolling unit 210 may detect the position of objects such as eyes, ora nose using face recognition algorithm, and obtain aligning homogeneousmatrix.

The vision controlling unit 210 may set a region of interest (ROI) onthe surface of the object 400 in the three-dimensional image.

The region of interest (ROI) may be a region including a portion that ofrequiring the laser irradiation, and set the region of interest (ROI)may be set by the user (e.g., physician), or may be automatically set bythe three-dimensional image process.

For example, the user may set the region of interest (ROI) by clickingon the four corner points on the facial surface, and in this case, thenormal vector corresponding to each of the corner point may be obtained.

On the other hand, the vision controlling unit 210 may determine atleast one of the color or the contrast of the surface of the object 400based on the data transmitted form the scanner 300, and set the regionof interest based on the determined result.

Specifically, the vision controlling unit 210 may detect a portion wherethe color or/and the contrast of the surface of the object 400 is (orare) different form the two-dimensional color image of the object 400photographed by the scanner 300. In addition, the vision controllingunit may set the region of the interest to be included the other portionwhere the color and/or contrast is (or are) different than anotherportion.

More specifically, the reason for darkly appearing a specific portion ismainly due to the pigment of the depth of the blood vessels, otherwisedue to the shaded region by the contour of the skin.

Therefore, an algorithm may be applied to distinguish the regions whichdarkly appear due to the pigment or blood vessels of the face or darklyappear in the shade region due to the contour of the skin, and thedermatological treatment method may be changed depending on thisdistinction.

For example, if the shaded region, caused by the contour of the skin, isoccurred, it is caused by the skin stain or the atrophy of thesubcutaneous fat layer due to skin aging, thereby treating firmnesstreatment, fac implants, fillers, and the like.

Further, when the shaded region caused by the scar is occurred, it maybe necessary the scar treatment.

In the following, it may be referred to as a region of therapy (ROT)which is necessary for treatment by irradiating the laser on the surfaceof the object.

For example, the region of therapy (ROT) may be liver spots, freckles,burn marks, tattoos, acne, dark circles, and the like, those areoccurred in the human skin, the present invention is not limited tothis, and it may be treatable regions by irradiating the laser ofvarious kinds of wavelength or frequency.

The vision controlling unit 210 may determine this portion where colorand/or contrast are different surroundings as the region of therapy(ROT).

According to an embodiment of the present invention, the region ofinterest (ROI) and the region of therapy (ROT) may be set separately asdescribed above, but may be set only the region of therapy (ROT) whichis actually irradiated as needed.

The vision controlling unit 210 constitutes a motion pattern on theobject for the laser treatment on the basis of the determined (or set)information as described above, and the motion pattern may be configuredby setting the guide path (GP) passing through the region of interest(ROI) or the region of therapy (ROT).

Then, the vision controlling unit 210 sets a plurality of pointsarranged on the guide path (GP). The plurality of points may representthe position where the laser is irradiated on the surface of the object,and the point on the guide path (GP) displayed on the two-dimensionalimage may be projected on the three-dimensional image.

In addition, the vision controlling unit 210 obtains the actual laserirradiation points to be irradiated on the surface of the object byselecting only those points positioned within the region of therapy(ROT) of the plurality of points arranged on the guide path (GP).

The motion controlling unit 220 controls the operation of the robot arm100 on the basis of the information obtained by the vision controllingunit 210, while the end-effector 101 irradiates the laser as closelymoving to the surface of the object.

Here, the interval between the surface of both the end-effector 101 andthe surface of the object during the laser irradiation are preferablyand constantly maintained during the movement, the interval may be setbased on a focal distance of the laser.

For example, the motion controlling unit 220 may control the movementand the laser irradiation of the robot arm 100 on the basis of the guidepath (GP) and the laser irradiation points set in the vision controllingunit 210.

In addition, the motion controlling unit 220 may emergently stop thelaser irradiation by urgently stopping the robot arm 100, for example,the operation of the robot arm 100 may be stopped by the action or thevoice of the doctor or the patient.

The laser irradiation apparatus 10 according to the present inventionmay each operate in a manual mode or an automatic mode.

For example, in the automatic mode, the scanner 300 scans the surface ofthe object 400 to obtain the information about the surface of the object400, and the controlling unit 200 may irradiate with the laser on thesurface of the object 400 by controlling the robotic arm 100 on basis ofthe obtained information.

On the other hand, in the manual mode, the user such as a doctor has thecontrolling authorization, the robot arm 100 is operated by the controlof the user.

It has been described for the configuration of the laser irradiationapparatus with FIGS. 1 to 3 as described above, the present inventionshall not be limited, and some of the illustrated elements may beomitted or added additional elements as needed.

For example, the laser irradiation apparatus 10 further includes acomputing unit (not shown) for performing a function of ArtificialIntelligence (AI) and a database (not shown) for processing big data.

The laser irradiation method using the laser irradiation apparatus 10according to the present invention will be described in detail withreference to the accompanying drawings.

FIGS. 4 to 25 are views for explaining the operation of the laserirradiation apparatus according to embodiments of the present invention,the same explanation as explained with reference to FIGS. 1-3 of theoperation and the construction of the laser irradiation apparatus 10will be omitted below.

Referring to FIG. 4, the controlling unit determines whether the currentsetting mode is the automatic mode or not or not (step S100). If theautomatic mode is not, the controlling unit determines whether thecurrent setting mode is the manual mode or not (S110).

For example, the user may set by selecting one of the manual mode or theautomatic mode using a button mounted in the laser irradiation apparatus10 or a user interface (UI) provided in a touch screen.

It is determined that if the current setting mode is not the manual modein the step S110, it is performed a different function previouslypredetermined (for example, Default setting) (S120).

On the other hand, if the current setting mode is the manual mode, it isdetermined that the setting status of the manual mode (S130), thecontrolling authorization is given to the user (S140).

Here, the operation of giving the controlling authorization to the usermeans that the controlling unit 200 may judge for themselves and limitthe operation of the robot arm 100.

In the manual mode, the user may operate the robotic arm 100 on theirown while performing the laser treatment.

On the other hand, it is determined that the current setting mode is theautomatic mode in the step S100, the scanner 300 scans the surface ofthe object 400 according to the control of the controller 200 (S150). Asa result of the scanning by the scanner 300, the raw data including thetwo-dimensional image and the depth information may be generated.

Here, a screen mode is available to be moved the irradiation position ofthe laser along the motion of the pointer on a monitor.

Then, the vision controlling unit 210 constitutes the three-dimensionalimage on the basis of the raw data obtained from the scanner 300 (S160).

For example, the canner may scan a plaster cast of a head shape of aperson, as shown FIG. 5(A), it may be constituted the three-dimensionalimage as shown FIG. 5(B).

Hereinafter, for convenience of explanation, it will be described wherethe plaster cast of the head shape is regarded as the object 400.

After constituting the three-dimensional image, the region of interest(ROI) is set on the surface of the object 400 in the three-dimensionalimage (S170).

For example, the first corner point (Pcor, 1), the second corner point(Pcor, two), the third corner point (Pcor, 3), and the fourth cornerpoint (Pcor, 4) may be set on the surface of the object 400 in thethree-dimensional image, as shown in FIG. 5 (C). Then, the region ofinterest (ROI) may be set with a region partitioned by the vertices withfour corner points such as the first, the second, the third and the fourcorner points.

In this embodiment, the region of interest (ROI) is set using the fourcorner points, but the number of corner points to be used the conditionsmay be changed. For example, it is possible to set the region ofinterest (ROI) by using at least three corner points.

Hereinafter, the first corner point (Pcor, 1), the second corner point(Pcor, two), the third corner point (Pcor, 3), and the fourth cornerpoint (Pcor, 4) may be referred as the first point (P1), the secondpoint (P2), the third point (P3), and the fourth point (P4),respectively.

Then, the guide path (GP) passing through the region of interest (ROI)may be set (step S180).

For example, as illustrated in FIG. 6, it is possible to set the guidepath (GP) within the region of interest (ROI).

The starting point of the guide path (GP), i.e. the point at which thelaser irradiation is started, is expressed as Ps, while the end point ofthe guide path (GP), i.e. the point at which the laser irradiation isended, is expressed as Pt.

Then, the laser is irradiated in sequence to the laser irradiationpoints on the surface of the object corresponding to the guide path (GP)(Step S190).

The guide path (GP) may include a path where the robot arm 100 isirradiated with the laser. In other words, the robot arm 100 mayirradiate with the laser to the surface of the object as moving inresponse to the guide path (GP).

The guide path (GP) may be regarded as including a path connecting thehitting point of the laser.

On the other hand, the regions of interest (ROI) may be set based on atleast one a color, contrast, contour and texture of the surface of theobject 400. It will be explained with reference to FIG. 7 as follows.

Referring to FIG. 7, in S170 step of setting the region of interest(ROI), the color and/or contrast of the surface of the object 400 isfirstly determined (step S171). Here, the color and/or contrast of thesurface of the object 400 may be determined from the two-dimensionalcolor image of the object 400.

Since, the determined value is compared with the reference value (S172step), the region of therapy (ROT), which is different surroundings atleast one of contrast and contour, is detected from the surface of theobject 400 according to the comparison result (step S173).

For example, a region of normal (RON) and the region of therapy (ROT)may be distinguished on the basis of at least one of a color, contrast,contour and texture on the surface of the object 400.

As shown in FIG. 8, when the total 16 of unit areas are arranged in 4×4matrix form, the number expressed on each of the unit area may indicatethe brightness value.

Here, it is assumed that the brightness value is 40, it is determinedthe region of therapy (ROT) with unit areas of (1, 1), (2, 1), (3, 1),(3, 2), (3, 3), (3, 4), (4, 1), (4, 2), (4, 3) and (4, 4) that thebrightness value is smaller than 40, and the remained portion may bedetermined as the region of normal (RON).

The brightness of the region of therapy (ROT) may appear relativelydarker than other portion, that is lower than the brightness of theregion of normal (RON). Similarly, the color of the region of therapy(ROT) may appear relatively thicker than the color of the region ofnormal (RON). The thicker color means more darker than surroundings.

As such, the brightness value of the region of therapy (ROT) may be alower portion than a predetermined reference brightness value. Thereference brightness value may be varied in various ways depending onthe surface state or characteristics (for example, contour or texture,etc.) of the object 400 or other factors such as the color tone.

Here, the reference brightness value may be a constant, but preferablymay be set differently for each patient or treatment region. Forexample, the reference brightness value may be varied by considering abrightness value of the surrounding region to coincide the skin tonewith a region adjacent to the region of therapy (ROT).

If the face of White is bright as a whole, the reference brightnessvalue may be set relatively high based on the brightness value. Thereason is that if the face is appeared with bright white as a whole, aportion requiring the treatment such as dots, spots required, i.e. theregion of therapy, is more prominently appeared.

On the other hand, if the face is Mongoloid appeared relatively dark asa whole than Whites, the reference brightness value may be setrelatively low compared with the brightness value of Whites.

After detecting the region of therapy (ROT), then the regions ofinterest (ROI) is set (S174).

As described above, the region of interest (ROI) includes the region oftherapy (ROT), the region of interest (ROI) and the region of therapy(ROT) may be equally set.

As illustrated in FIG. 9(A), it is assumed that the region of therapy(ROT), where brightness, color, contour, and texture, etc. are differentwithin the region of normal RON, is included on a predetermined region(R1) of the surface of the object 400, the form of the region of therapy(ROT) is arbitrarily set for convenience of the description and thepresent invention is not limited thereto.

In this case, as illustrated in FIG. 9(B), it may be set the first,second, third, and fourth points (P1, P2, P3, and P4) to be contactedthe first line (L1) connecting the first point (P1) and the second point(P2) with the region of therapy (ROT), the second line (L2) connectingthe second point (P2) and the fourth point (P4) with the region oftherapy (ROT), the third line (L3) connecting the third point (P3) andthe fourth point (P4) with the region of therapy (ROT), and the fourthline (L4) connecting the fourth point (P4) and the first point (P1) withthe region of therapy (ROT).

In addition, regions divided with the first, the second, the third, andthe fourth points (P1, P2, P3, and P4) may be set as the region ofinterest (ROI).

Here, the region of therapy (ROT) may be also included inside of theregion of normal (RON), the region of interest (ROI) may include oneportion of the region of normal (RON) as well as the region of therapy(ROT).

Hereinafter, it is assumed that a portion included within the region ofinterest (ROI) in the region of normal (RON) is a second region ofnormal (RON2) and the other portion does not include within the regionof interest (ROI) in the region of normal (RON) is a first region ofnormal (RON1).

In the case of FIG. 9, as setting the region of interest (ROI), it isdescribed only one case that a line connecting two near points iscontacted on the region of therapy (ROT), the present invention may notbe limited thereto.

For example, as in a case of FIG. 10, at least one or all lines (L1, L2,L3, and L4) connecting two near points is (or are) not in contact withthe region of therapy (ROT).

Thus, the method of setting the region of interest (ROI) may be changedin various ways.

In case that the shape of the region of therapy (ROT) is the polygonalshape, it may be occurred that the region of therapy (ROT) and theregion of interest (ROI) are same depending on the set position of thepoint.

On the other hand, the guide path (GP) is capable of being set withinthe region of therapy (ROT).

For example, it is possible to set the guide path (GP) with the zigzagform within the region of therapy (ROT), as shown in FIG. 11.

As such, the guide path (GP) is passing through the region of therapy(ROT), the laser is capable of being irradiated in the region of therapy(ROT).

On the other hand, it is possible to control the fluence and/orfrequency of the laser in the beginning step and the end step of thelaser irradiation.

The fluence of the laser represents the laser energy (J/cm²) deliveredper unit area, it may means the strength or intensity of the laser. Andthe laser frequency may means the emission frequency of the laser.

Referring to FIG. 12(A), at least one of the fluence or frequency of thelaser is gradually raised in the beginning step of irradiating thelaser, while at least one of the fluence or frequency of the laser isgradually decreased in the end step of the irradiating the laser.

In the following description, the beginning step of the laserirradiation is referred to an acceleration section (D1), while the endstep of the laser irradiation is referred to a reduction section (D3).

As shown in FIG. 12(B), the moving speed of the robot arm 100 may beincreased in the acceleration section (D1). That is, the movement speedof the robot arm 100 may be accelerated.

The occurrence reason of the acceleration section (D1) is because ittakes some time from the time of supplying the power operating the robotarm 100 to the motor to the time of reaching the desired rotation speed.

In addition, in the deceleration section (D3), the moving speed of therobot arm 100 may be reduced. The reason why the deceleration section D3is generated is that it takes some time from the time of shutting outthe power supply to the motor operating the robot arm 100 to the stop ofthe motor similarly to the acceleration section D1.

In this way, when the fluence and/or frequency of the laser is graduallyrisen in acceleration section (D1) and is gradually decreased in thedeceleration section (D3), it may be possible to uniformly irradiate thelaser.

The fluence and/or frequency of the laser may be substantiallyproportional to the moving speed of the robot arm 100.

At this time, a maintain section (D2) may be occurred between theacceleration section (D1) and the deceleration section (D3), the fluenceand/or frequency may substantially and constantly be maintained in themaintain section (D2) if the laser irradiation is not stopped.

The speed of the robot arm 100 may be substantially and constantlymaintained in the maintain section (D2), for example, the speed of thearm 100 may be constantly maintained during the section (D2) from thetime at which the acceleration of the robot arm 100 is ended to the timeat which the deceleration is started.

As shown in FIG. 13(A), it may be possible that of increasing with stepcurve the fluence and/or frequency of the laser in the accelerationsection (D1) or decreasing in the deceleration section (D3).

In this case, it may be considered to gradually raise the fluence and/orfrequency of the laser in the acceleration section (D1), and graduallydecrease the fluence and/or frequency of the laser in the decelerationsection (D3).

On the other hand, the guide path (GP) may be possible to deviateoutside the region of therapy (ROT) within the region of interest (ROI).

For example, as shown in FIG. 14 when the region of interest (ROI)include the region of therapy (ROT) and the region of normal, i.e., thesecond region of normal (RON2), the guide path (GP) may be passed allregions of the region of therapy (ROT) and the second region of normal(RON2).

In this case, the robot arm for irradiating the laser is turned on incorrespondence to the region of therapy (ROT) or turned off incorrespondence with the second region of normal (RON2). Thus, it ispossible to set the guide path (GP) without the relationship of theshape of the region of therapy (ROT) within the region of interest(ROI).

Further, the guide path (GP) includes a portion passing through theregion of therapy (ROT) and the other portions (T1, T2, T3, and T4)passing through the region of normal (RON2) deviating outside the regionof therapy (ROT).

As shown in FIG. 15, the robot arm 100 may turn off the laserirradiation corresponding to the portion passing through the secondregion of normal (RON2) in the guide path (GP). In other words, it isconsidered that the robot arm 100 may turn on/off the laser irradiationdepending on at least one color, brightness, and contour of the surfaceof the object 400 in the course of irradiating the laser along the guidepath (GP).

That is, the robot arm 100 moves corresponding to the guide path (GP)and may turn on the laser irradiation corresponding to the portion,where the color is appeared more darker or the brightness is lower thanthe surroundings, that is the region of therapy (ROT) and turn off thelaser irradiation corresponding to the portion, where the color isappeared more lighter or the brightness is higher than the surroundings,that is the region of normal (RON).

Referring to FIG. 15, it may be known that the laser frequency and/orfluence is set substantially zero in the portions (T1, T2, T3, and T4)where the robot arm 100 is passing through the second region of normal(RON2).

In this case, the movement of the robot arm is possible to maintainsubstantially and constantly, thereby improving the accuracy of thetreatment.

On the other hand, it is possible to adjust at least one of thefrequency, the irradiation time, the number of the laser irradiation,the fluence of the laser depending on the degree of color and/orbrightness of the region of therapy (ROT) under the control of themotion controlling unit 220.

Referring to FIG. 16, the region of therapy (ROT) may include the firstregion of therapy (ROT1) and the second region of therapy (ROT2).

Here, the color of the second region of therapy (ROT2) may be darkerthan the first region of therapy (ROT1), or the brightness of the secondregion of therapy (ROT2) may be lower than the brightness of the firstregion of therapy (ROT1).

Alternatively, the brightness of the second region of therapy (ROT2) maybe lower than the critical brightness value predetermined in advance,while the brightness of the first region of therapy (ROT1) may be higherthan the critical brightness value predetermined in advance.

In this case, the second region of therapy (ROT2) may be considered as aportion required intensive care compared to the first region of therapy(ROT1).

In this embodiment of the present invention, it is referred to as thefirst point X1 for a boundary point between the second region of normal(RON2) and the first region of therapy (ROT1) on the guide path (GP) assequentially moving at the starting point Ps of the laser, the secondpoint X2 for a boundary point between the first region of therapy (ROT1)and the second region of therapy (ROT2), the third point X3 for aboundary point between the second region of therapy (RON2) and thesecond region of normal (ROT2), the fourth point X4 for a boundary pointbetween the second region of normal (RON2) and the first region oftherapy (ROT1), the fifth point X5 for a boundary point between thefirst region of therapy (ROT1) and the second region of therapy (ROT2),the sixth point X6 for a boundary point between the second region oftherapy (ROT2) and the first region of therapy (ROT1), the seventh pointX7 for a boundary point between the first region of therapy (ROT1) andthe second region of therapy (ROT2), and the eighth point X8 for aboundary point between the second region of therapy (ROT2) and the firstregion of therapy (ROT1).

As shown in FIG. 17, the robot arm may turn off the laser irradiation insections from the start point (Ps) of the laser to the first point (X1)and from the third point (X3) to the fourth point (X4), respectively.

For example, since Ps-X1 section and X3-X4 section are included in thesecond region of normal (RON2), thus the robot arm 100 may not irradiatethe laser.

On the other hand, the frequency of the laser is set at the firstfrequency (f1) in X1-X2 section, X4-X5 section, X6-X7 section and thesection from the eighth point (X8) to the beginning of the decelerationsection (D3).

And, it may be gradually varied the gradation of the irradiationconditions through the variations of the laser irradiation frequency orthe laser irradiation fluence by the variation in velocity of theend-effector 101, or the adjustment of the laser fluence or pulseduration in X1, X3 and X4 points.

Further, in the other points except X1, X3 and X4 points, the gradationof the irradiation conditions as described above may be graduallyachieved.

On the other hand, in X2-X3, X5-X6, and X7-X8 sections, the frequency ofthe laser may set with a second frequency (f2) that is higher than thefirst frequency (f1).

In this case, the laser, which is relatively stronger, may be irradiatedon the second region of therapy (ROT2) thereby improving the treatmentefficiency.

Referring to FIG. 18(A), the frequency of the laser may equally set asthe first frequency (f1) in X1-X3 section, X4-X8 section and a sectionfrom the eighth point (X8) to the beginning of the deceleration section(D3).

Thus, while maintaining the frequency of the laser, as shown in FIG.18(B), the movement speed of the robot arm 100 may set at the firstspeed (V1) in a section from a point of the end of the accelerationsection D1 to the second point X2, X3-X5 section, X6-X7 section, and thesection from the eighth point (X8) to the beginning of the decelerationsection (D3).

On the other hand, the movement speed of the robot arm 100 may be set atthe second speed (V2) which is slower than the first speed (V1) inX2-X3, X5-X6, and X7-X8 sections.

In this case, the laser may irradiate relatively longer than the secondregion of therapy (ROT2) thereby improving the treatment efficiency.

That is, in the case that the speed of the end-effecter (EE) and thefluence of the laser are constant and the emission frequency of thelaser is higher, the overlapping rate of the laser is relatively higherin the second region of therapy (ROT2), thereby providing more amount ofthe laser energy.

On the other hand, for the second region of therapy (ROT2), the numberof treatments may be set a lot more than the first region of therapy(ROT1). For this, it will be described below referring to FIG. 19.

FIG. 19(A) shows the status that the robot arm 100 may irradiate thelaser for the first laser treatment on the surface of the object 400along the guide path (GP) within the region of interest (ROI), whileFIG. 19(B) shows the status that of performing the second laserirradiation carried out after the end of the first laser treatment.

Referring to FIG. 19(A), the robot arm 100 may irradiate the laser inX1-X3 section, X4-X8 section and a section from the eighth point (X8) tobefore the deceleration section (D3), in which the frequency of thelaser may be equally set at the first frequency (f1).

Referring to FIG. 19(B), in the second course of the laser treatment,the robotic arm 100 may irradiate the laser in X2-X3 section, X5-X6section, and X7-X8 section corresponding to the second region of therapy(ROT2), in which it may be equally set to the frequency of the lasercorresponding to the difference between the second frequency (f2) andthe first frequency (f1).

Thus, the therapeutic effect similar to that of irradiating the laser ofthe second frequency (f2) may be occurred in the second region oftherapy (ROT2).

Referring to FIG. 20, it is possible to set the guide path (GP) ofhelical type to start from the central region of the region of interest(ROI) and to end at the outer periphery. That is, the starting point(Ps) of the guide path (GP) may be located in the central region of theregion of interest (ROI) relatively more than the end point (Pt).

Thus, if the guide path (GP) is set to be the helical type, the robotarm 100 is prevented from suddenly changing directions, so that thelaser may be more uniformly irradiated to the surface of the object 400.

Even in the case of setting the guide path (GP) of helical type, asshown in FIG. 21, the guide path (GP) may pass through both the secondregion of normal (RON2) and the region of therapy (ROT) together.

In this case, the laser irradiation may be turned off at the portions(T11, T12, and T13) passing through the second region of normal (RON2)on the guide path (GP).

Referring to FIG. 22, it is also possible that the guide path (GP) maybe out of the region of interest (ROI). In such a case, the therapeuticeffect may be enhanced by irradiating more densely the laser onto theregion of therapy (ROT).

It is possible to turn off the laser irradiation corresponding to aportion that deviates from the region of interest (ROI) on the guidepath (GP).

The shape of the guide path (GP) may be variously changed under thespiral condition.

For example, as in the case of FIG. 23, it is possible to set the guidepath (GP) with the elliptical shape when the region of therapy (ROT) isformed with the elliptical shape.

According to the present invention, as in the case of FIG. 24, theend-effector 101 of the robot arm 100 preferably irradiates the laserapproximately perpendicular to the surface of the object 400 to increasethe therapeutic efficacy and to improve the treatment accuracy.

To this end, the robot arm 100 may be desirable with degree of freedom(DOF). Specifically, the robot arm 100 may be desirable to have fivedegrees of freedom, and it is preferably have at least six degrees offreedom for exceptional circumstances.

FIG. 25 illustrates the structure of the laser irradiation apparatusaccording to an embodiment of the present invention. The laserirradiation apparatus includes a laser emitter, a motor, a motor drive,a reflection mirror, and an end effector (EE) irradiate the laser ontothe surface of the object 400, that is the plaster cast of the headshape.

The laser irradiation experiment conducted by using the laserirradiation apparatus 10 according to the present invention is describedin FIGS. 21 and 22.

Referring to FIG. 21, it is disclosed an example that the robot arm 100,including a laser emitter, a motor, a motor drive, a reflecting mirrorand an end-effector (EE), irradiates the laser onto the surface of theobject 400 that is the plaster cast of head shape.

Referring to FIG. 25, the motor and the motor drive operate the robotarm 100. When the laser emitter irradiates the laser, the reflectionmirror reflects the laser at a predetermined angle to reach theend-effector (EE), the end-effector (EE) connected to the end terminalof the robot arm 100 may irradiate the laser on the surface of theobject 400.

For example, the motor and the motor drive may be controlled by themotion controlling unit 220 so that the end-effector (EE) is moved alongthe guide path (GP) set by the vision controlling unit 210.

In addition, the laser emitter may be controlled by the motioncontrolling unit 220 so that the laser is irradiated onto the laserirradiation points set by the vision controlling unit 210.

The motors and the motor drive may operate the robot arm 100.

When the laser emitter is emitted the laser, the reflecting mirror mayreflect at a predetermined angle thereby reaching the laser to theend-effector.

Then, the end-effector may irradiate the laser on the surface of theobject 400.

Referring to FIG. 22, it may be confirmed that the guide path (GP) isset in the spiral on the surface of the object 400. FIG. 22 shows thatit is photographed the laser irradiation on the surface of the object400 in a constant duration and implemented by the shape of the guidepath (GP).

On the other hand, it is possible to stop the laser irradiationdepending on the conditions or to modify the guide path. The detailedexplanation will be described as follows.

Referring to FIG. 23, the motion of the object 400 may be determinedafter setting the guide path (GP) or irradiating the laser (S200). Forexample, if the object 400 is a person's head, it may be determinedwhether there is a motion in a corresponding section or not by lookingat a specific portion such as a nose, both eyes. Or, if the surface ofthe object 400 is moved, for example, the skin of a person is movedcause by the reasons such as convulsions in the skin of a person's face,it may be considered that the movement of the object 400 is exist.

As determined result, if there is no motion of the object 400, it may bemaintained a predetermined guide path (GP) (S210).

On the other hand, if it is determined that the motion of the object 400may be measured, it may measure the amount of motion of the object (400)(S220). The measurement of the amount of motion of the object 400 meansto be determined that how long the object 400 is moved.

It is determined that whether the motion amount exceeds a thresholdrange previously set or not as the result of measuring the motion amount(S230).

It determined that, if the motion amount of the object 400 is greaterthan the threshold range previously set, it is possible to perform theemergency stop mode (S240). In this case, it is possible to urgentlystop the laser irradiation.

On the other hand, if the motion amount of the object 400 does notexceed the threshold range, the region of interest (ROI) may be reset inconsideration of the motion amount (S250).

In this embodiment, it is considered that the motion controlling unit220 compensates or corrects the guide path, when the scanner 300collects the motion of the object 400 and the vision controlling unit210 newly reset the region of interest (ROI).

In addition, the guide path (GP) may also be modified corresponding tothe reset of the region of interest (ROI) (S260).

For example, as in the case of FIG. 24, if the object 400 is movedtoward left upper side 1 cm, then the region of interest (ROI) is alsomoved toward the left upper side 1 cm. Correspondingly, the guide path(GP) may also be moved toward the upper left 1 cm.

Then, the laser may be irradiated on the surface of the object 400corresponding to the modified guide path (GP) (S270).

As such, if the motion of the object 400 is occurred in the lasertreatment process, it may be possible to modify the guide path (GP) inreal time according to the motion of the object 400.

On the other hand, in the above description, it is described theembodiment as below that the object 400 is moved up, down, left or righton the same plane, it may be also be adapted when moving back and forthby maintaining the interval between the end-effecter (EE) of the laserirradiation apparatus and the surface of the object 400.

In case that the vibration is generated and the force is applied in thelaser irradiation apparatus 10, it is possible to perform the emergencystop mode.

For example, as shown in FIG. 25, it may be determined that whether thevibration is generated or the force is applied or not after setting theguide path (GP) or irradiating the laser (S300).

As determined result, if the vibration is not generated or the force isnot applied, it may be maintained the predetermined guide path (GP)(S310).

On the other hand, it is determined that the vibration is generated, orthe force is applied, it may measure the vibration and/or the force(S320).

As the measured result, it may be determined that whether the vibrationis generated more than a reference value previously set, or applied theforce more than a threshold value previously set (S330).

As the measured result, if the vibration is generated more than thereference value, or applied the force more than the threshold value, itmay perform the emergency stop mode (S340). In this case, it is possibleto urgently stop the laser irradiation.

On the other hand, if the vibration is generated less than the referencevalue, or applied the force lower more than the threshold value, it mayreset the region of interest (ROI) in consideration of the vibrationand/or the force (S350).

In addition, the guide path (GP) may also be modified corresponding tothe reset of the region of interest (ROI) (S360).

Then, the laser may be irradiated on the surface of the object 400corresponding to the modified guide path (GP) (S370).

For example, the laser irradiation apparatus 10 may be urgently stoppedto cease the laser irradiation where the vibration equal to or largerthan the reference value is generated in the robot arm 100 when someonetouches the laser irradiation apparatus or touches a table on which thepatient is lying, or an earthquake occurrence in the course of thetreatment procedure. Alternatively, the laser irradiation apparatus 10may be urgently stopped to stop the laser irradiation, during thetreatment procedure, the user (doctor or the like) finds a procedureerror and holds the robot arm 100 by hand thereby applying the forceequal to or greater than a threshold value to the robot arm 100.

When the robot arm 100 having a predetermined degree of freedom isoperated as described above and the laser is sequentially irradiatedalong the guide path (GP) on the surface of the object through the endeffector EE, It is preferable that the guide path (GP) is set so thatthe operation of the robot arm 100 may be easily controlled.

Although the embodiment of the present invention has been described withreference to the laser irradiation apparatus using the robot arm, butthe present invention is not limited thereto. In addition, it may beapplicable to control movement patterns in various types of apparatus ofa gantry type laser irradiation apparatus for wrapping a patient's bodyface or the laser irradiating apparatus in the shape of a laser arraypatch attached to a patient's face.

Further, although the present invention is described as the example withreference to the laser irradiation apparatus using the robot arm, thetechnical construction of the present invention may be applicable to avariety of energy based medical device, for treating the skin, using thehigh frequency, ultrasound, IPL (Intense Pulse Light), Psoralen-UV-A(PUVA), etc.

The laser irradiation methods using a robot arm according to the presentinvention may be stored in a computer-readable recording mediummanufactured as a program to be executed in a computer, examples of thecomputer-readable recording medium include ROM, RAM, CD-ROM, a magnetictape, a floppy disc, optical data storage devices, and it is implementedin the form of carrier waves (such as data transmission through theInternet).

Further, the computer-readable recording medium is distributed overnetwork coupled computer systems so that the computer readable code isstored and executed in a distributed fashion. Then, the functionalprograms, codes, and code segments for accomplishing the presentinvention can be easily construed by programmers skilled in the art towhich the invention pertains.

In this way, the above-described technical construction of the presentinvention it will be appreciated that without the person skilled in theart changing the technical spirit or essential features of the inventionmay be embodied in other specific forms.

Therefore, the embodiment described in the above examples should beunderstood as not be illustrative and not restrictive in all respects,and becomes the scope of the invention is indicated by the claims belowrather than the foregoing description, the meaning and scope of theclaims and all such modifications as derived from the equivalent conceptbe construed as being included in the scope of the invention.

What is claimed is:
 1. A laser control method comprising: a setting stepof setting a guide path on a surface of an object; and an irradiatingstep of irradiating a laser onto the surface of the object correspondingto the guide path, wherein at least one of a fluence or a frequency ofthe laser is gradually increased at the beginning stage of the laserirradiation and at least one of the fluence or the frequency of thelaser is gradually decreased at the end of the laser irradiation.
 2. Thelaser control method according to claim 1, wherein the laser isirradiated from an end-effector mounted on a robot arm.
 3. The lasercontrol method according to claim 2, wherein the robot arm isaccelerated at the beginning stage of the laser irradiation, and therobot arm is decelerated at the end stage of the laser irradiation. 4.The laser control method according to claim 3, wherein the speed of therobot arm is constantly maintained during a period from the end stage ofthe acceleration to the start stage of the deceleration of the robotarm.
 5. The laser control method according to claim 1, wherein the laserirradiation is turned on/off depending on at least one of color orbrightness of the surface of the object in the laser irradiation step.6. The laser control method according to claim 1, the method furthercomprising: collecting raw data by scanning the object; constituting athree-dimensional image of the object based on the raw data; setting aregion of interest (ROI) on the surface of the object in thethree-dimensional image; and setting the guide path passing through theregion of interest (ROI).
 7. The laser control method according to claim6, wherein the raw data includes a two-dimensional image and a depthinformation.
 8. The laser control method according to claim 7, whereinthe step of setting the region of interest (ROI) comprising:distinguishing a region of normal and a region of therapy on the basisof at least one of a color and a brightness on the surface of theobject; and setting the region of interest to include the region oftherapy, wherein the color of the region of therapy is thicker than acolor of the region of normal, or the region of therapy is darker thanthe region of normal.
 9. The laser control method according to claim 8,wherein the guide path passes through the region of therapy, and thelaser is irradiated onto the region of therapy.
 10. The laser controlmethod according to claim 8, wherein the region of interest comprisesthe region of therapy and the region of normal; the guide path passesthrough both the region of therapy and the region of normal; the laserirradiation is turned on in response to the region of therapy and turnedoff in response to the region of normal.
 11. A laser irradiationapparatus comprising: a motion controlling unit for setting a guide pathon a surface of an object; and a robot arm, mounted with anend-effector, for applying a laser to the surface of the objectcorresponding to the guide path, wherein at least one of a fluence or afrequency of the laser is gradually increased at the beginning stage ofthe laser irradiation and at least one of the fluence or the frequencyof the laser is gradually decreased at the end of the laser irradiation.12. The laser irradiation apparatus according to claim 11, wherein therobot arm is accelerated at the beginning stage of the laserirradiation, and the robot arm is decelerated at the end stage of thelaser irradiation.
 13. The laser irradiation apparatus according toclaim 12, wherein the speed of the robot arm is constantly maintainedduring a period from the end stage of the acceleration to the startstage of the deceleration of the robot arm.
 14. The laser irradiationapparatus according to claim 11, wherein the laser irradiation is turnedon/off depending on at least one of a color or a brightness of thesurface of the object in the laser irradiation step.
 15. The laserirradiation apparatus according to claim 11, the apparatus furthercomprising: a scanner for collecting a raw data by scanning the object;and a vision controlling unit for constituting a three-dimensional imageof the object based on the raw data, setting a region of interest (ROI)on the surface of the object in the three-dimensional image; wherein themotion controlling unit sets the guide path passing through the regionof interest (ROI).
 16. The laser irradiation apparatus according toclaim 15, wherein the raw data includes a two-dimensional image and adepth information.
 17. The laser irradiation apparatus according toclaim 16, wherein the vision controlling unit distinguishes a region ofnormal and a region of therapy on the basis of at least one of a colorand a brightness on the surface of the object, and sets the region ofinterest to be included the region of therapy, wherein the color of theregion of therapy is thicker than a color of the region of normal, orthe region of therapy is darker than the region of normal.
 18. The laserirradiation apparatus according to claim 17, wherein the guide pathpasses through the region of therapy, and the laser is irradiated ontothe region of therapy.
 19. The laser irradiation apparatus according toclaim 17, wherein the region of interest comprises the region of therapyand the region of normal; the guide path passes through both the regionof therapy and the region of normal; the laser irradiation is turned onin response to the region of therapy and turned off in response to theregion of normal.